Recording apparatus and reproducing apparatus

ABSTRACT

It is an object of the present invention to provide a recording apparatus and a reproducing apparatus which change a picture compression rate depending upon a picture quality of a source which a user desires to retain, thereby a tape storage space being secured. A video-data compression rate N used by a 1:N video-data compression encoder  3  and a 1:N video-data compression decoder  6  is changed depending upon a picture quality set by a device  5  for setting a picture quality that a user desires. A tape travel speed of an archive VTR  4  is changed in response to the picture compression rate. Thus, an amount of a tape travel is optionally set depending upon a level of the picture quality. Therefore, it is possible to optionally select a tape storage space in response to the level of the picture quality.

TECHNICAL FIELD

The present invention relates to a recording apparatus and a reproducingapparatus suitable for use in the archiving for keeping a source taperetained for reproduction in a broadcasting station or the like.

BACKGROUND ART

In the prior art, a television broadcasting station, a production houseand so on have retained a tape on which a broadcasting program isrecorded by using the same tape as an original source tape and the sameformat.

Therefore, if different formats are employed, video tape recorders(VTRs) and their peripheral equipments of many kinds corresponding tothe original formats must be prepared for the archiving of keeping thesource tape retained for reproduction, and must always be maintained.

Some of such-equipments are old type ones which are difficult to bemaintained. For example, a type-B VTR is one of such equipments.

Since such archiving requires the tapes which are as much as the sourcetapes, a sufficient retention place used for retaining the tapes must beprepared.

In such conventional archiving system, since the archiving is carriedout by using the same tape as the source tape and the same format, thereis then the disadvantage that if different formats are employed, videotape recorders and their peripheral equipments of many kindscorresponding to the original formats must be prepared for the archivingof keeping the source tape retained for reproduction, and must always bemaintained.

In the conventional archiving system, since its archiving requires thetapes which are as much as the source tapes, a sufficient retentionplace used for retaining the tapes must be prepared.

DISCLOSURE OF THE INVENTION

The present invention is made in view of such aspects, and its firstobject is to provide a recording apparatus and a reproducing apparatuswhich change a picture compression rate depending upon a picture qualityof a source which a user desires to retain, thereby a tape retentionspace being secured.

The present invention is made in view of such aspects, and its secondobject is to provide a reproducing apparatus which reduces a time forrecording a data string and allows a high-speed reproduction.

A recording apparatus according to a first invention includes avideo-data supply means for supplying a video data, a compression meansfor compressing the video data, a setting means for setting acompression rate used in the compression means, a control means forcontrolling a travel speed of a recording medium so that the recordingmedium should be traveled at a speed corresponding to the compressionrate set by the setting means, and a recording means for recording thevideo data compressed by the compression means on the recording medium.Therefore, it is possible to optionally select a tape retention space bychanging a tape travel speed in response to the video-data compressionrate.

According to a recording apparatus of a second invention, the controlmeans controls a speed of the recording medium so that a value of thecompression rate set by the setting means and the speed of the recordingmedium should be in proportion to each other. Therefore, the video-datacompression rate and the recording speed of the recording medium are inproportion to each other, which allows a recording time to be increasedin proportion to them.

According to a recording apparatus of a third invention, the controlmeans controls the speed of the recording medium so that, when thecompression rate set by the setting means is an inverse number of N(where N>1), the speed of the recording medium should be set to a speedobtained by multiplying the speed by an inverse number of N. Therefore,the video-data compression rate and the recording speed of the recordingmedium are set the same, which allows a recording time to be increasedin proportion to them.

According to a recording apparatus of a fourth invention, the recordingmeans records a compression rate data indicating the video-datacompression rate at the compression means on the recording medium.Therefore, the data of the compression rate set upon the recording canbe reproduced from the recording medium upon reproduction.

According to a recording apparatus of a fifth invention, the recordingmeans records a recording speed data indicating a recording speed of thevideo data at the recording means on the recording medium. Therefore,the data of the recording speed set upon the recording can be reproducedfrom the recording medium upon reproduction.

According to a recording apparatus of a sixth invention, the recordingmeans records a source ID data indicating the video data on therecording medium. Therefore, the data of the source ID data set upon therecording can be reproduced from the recording medium upon reproduction.

According to a recording apparatus of a seventh invention, thevideo-data supply means supplies a plurality of video data and therecording means records the plurality of video data compressed by thecompression means on respective channels of the recording medium.Therefore, it is possible to record a plurality of compressed datastrings on the recording medium with the data strings corresponding tospecific channels.

A reproducing apparatus according to an eighth invention is areproducing apparatus for reproducing a video data from a recordingmedium on which the video data and a travel-speed data indicating atravel speed of a recording medium obtained when the video data isrecorded thereon, including a reproducing means for reproducing thevideo data and the travel-speed data from the recording medium, acontrol means for controlling the travel speed of the recording mediumso that the recording medium should be traveled at a travel speedcorresponding to the reproduced travel-speed data, and an expandingmeans for expanding the reproduced video data at an expansion ratecorresponding to the travel speed data. Therefore, it is possible toreproduce the video data at a travel speed corresponding to thetravel-speed data recorded on the video data upon the recording and itis possible to expand the video data at the expansion rate correspondingto the travel-speed data.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a block diagram showing an embodiment of a recordingapparatus according to the present invention, and FIG. 1B is a blockdiagram showing an embodiment of a reproducing apparatus according tothe present invention;

FIG. 2 is a block diagram of a recording system of a data recorder usedin an archive VTR of the embodiment of the recording apparatus and thereproducing apparatus according to the present invention;

FIG. 3 is a diagram showing an outer data block DO output from an outererror code generating circuit of the recording system of the datarecorder used in the archive VTR of the embodiment of the recordingapparatus and reproducing apparatus according to the present invention;

FIG. 4 is a diagram showing memories MEM1, MEM2 of an arrangement of amemory of the recording system of the data recorder used in the archiveVTR of the embodiment of the recording apparatus and reproducingapparatus according to the present invention;

FIG. 5 is a diagram showing an inner data block D1 output from an innererror code generating circuit of the recording system of the datarecorder used in the archive VTR of the embodiment of the recordingapparatus and reproducing apparatus according to the present invention;

FIG. 6 is a diagram showing data maps MAP1, MAP2 output from a thirdmultiplexer circuit of the recording system of the data recorder used inthe archive VTR of the embodiment of the recording apparatus andreproducing apparatus according to the present invention;

FIG. 7 is a block diagram of a reproducing system of the data recorderused in the archive VTR of the embodiment of the recording apparatus andreproducing apparatus according to the present invention;

FIG. 8A is a diagram of one track of a recording information of theembodiment of the recording apparatus and reproducing apparatusaccording to the present invention, and FIG. 8B is a block diagram ofone sync. block of the recording information of the embodiment of therecording apparatus and reproducing apparatus according to the presentinvention;

FIG. 9 is a diagram showing a relationship between a recording rate anda tape travel speed according to the embodiment of the recordingapparatus and reproducing apparatus according to the present invention;

FIG. 10 is a diagram showing a relationship among the recording time, acompression rate and the tape travel speed of the embodiment of therecording apparatus and reproducing apparatus according to the presentinvention;

FIG. 11A is a block diagram of another embodiment of the recordingapparatus according to the present invention, and FIG. 11B is a blockdiagram of another embodiment of the reproducing apparatus according tothe present invention;

FIG. 12 is a block diagram of the recording apparatus of anotherembodiment of the recording apparatus and reproducing apparatusaccording to the present invention;

FIG. 13 is a block diagram of the reproducing apparatus of anotherembodiment of the recording apparatus and reproducing apparatusaccording to the present invention;

FIG. 14 is a diagram showing a track formed on a tape of anotherembodiment of the recording apparatus and reproducing apparatusaccording to the present invention;

FIG. 15 is a diagram showing a four-head system drum of anotherembodiment of the recording apparatus and reproducing apparatusaccording to the present invention;

FIG. 16 is a diagram showing a track formed on a tape of anotherembodiment of the recording apparatus and reproducing apparatusaccording to the present invention;

FIG. 17 is a block diagram showing a reproducing apparatus of anotherembodiment of the recording apparatus and reproducing apparatusaccording to the present invention;

FIG. 18 is a detailed block diagram showing a signal selection unit ofthe recording apparatus of another embodiment of the recording apparatusand reproducing apparatus according to the present invention; and

FIG. 19 is a timing chart of control of the signal selection unit of therecording apparatus of another embodiment of the recording apparatus andreproducing apparatus according to the present invention.

BEST MODE CARRYING OUT THE INVENTION

FIG. 1A is a block diagram showing an embodiment of a recordingapparatus according to the present invention. As shown in FIG. 1A, asource reproducing VTR 1 reproduces an existing source tape inaccordance with an existing format; e.g., it is a 1-inch omega VTR orthe like. An A/D converter 2 converts a video data reproduced by thesource reproducing VTR 1 into a digital value.

A 1:N video-data compression encoder 3 is a bit reduction encoder forcompressing the video data in ratio of 1:N (where N is variable andneeds not be an integer). At this time, a value of N is set dependingupon a requested picture quality set by a device 5 for inputting andsetting a picture quality that a user desires.

A formatter 9 converts a format of the video data reproduced by thesource reproducing VTR 1 into a data format of an archive VTR 4. Theformatter temporarily writes the converted video data in a buffer memoryincorporated therein and reads the video data written in the buffermemory, thereby supplying the video data to the archive VTR 4.

The archive VTR 4 further serves as a VTR for recording the video datacompressed by the 1:N video-data compression encoder 3 on a tape. Atthis time, a tape travel speed obtained when the archive VTR 4 recordsdata is set in accordance with a value of a compression rate N of thevideo data compressed by the 1:N video data compression encoder 3 Thevalue of the compression rate N of the video data, a recording channeland the tape travel speed obtained upon the recording are recorded in auser bit on a time code track. Alternatively, the value of thecompression rate N of the video data and the recording channel may berecorded in the user bit on the time code track with the correspondingtape travel speed being calculated from the compression rate N of thevideo data. The archive VTR 4 is controlled so that, by changing notonly its tape speed and but also its drum rotation speed, its frequencyshould be set the same as a frequency used when the tape was recorded.

FIG. 1B is a block diagram of one embodiment of the reproducingapparatus according to the present invention.

As shown in FIG. 1B, the archive VTR 4 reproduces a video data. At thistime, the archive VTR reads out a tape travel speed used when the videodata was recorded, from the user bit on the time code track, andreproduces the video data at the tape travel speed. The user sets achannel by a device 8 for inputting and setting a channel that the userdesires and the archive VTR retrieves an ID identifying a source toforwards the tape to that position. Then, the archive VTR reproduces thevideo data.

A 1:N video-data compression decoder 6 is a decoder for expanding avideo data compressed in the compression rate N of the video data inorder to restore to an original picture the compressed video datareproduced by the archive VTR 4. At this time, when the archive VTR 4reproduces the video data, the archive VTR detects the value of thecompression rate N of the video data compressed by the 1:N video-datacompression encoder 3 and recorded in the user bit on the time codetrack, and the 1:N video data compression decoder 6 expands thecompressed video data based on the detected value so that its dataamount should be N times as much as that of the data. Then, it ispossible to obtain the reproduced picture converted by a D/A converter 7into an analog value.

FIG. 2 shows an arrangement of a recording system of a data recorder ofan ID-1 format as the archive VTR. The ID-1 format is based on an ID-1format of ANSI (AMERICAN NATIONAL STANDARD 19 mm TYPE ID-1INSTRUMENTATION DIGITAL CASSETTE FORMAT) and determined with referenceto a D-1 format of a component digital VTR.

The recording system subjects an input information data to an errorcorrection coding of a product code type and then records them.

An outline of operations of respective circuits therein is as follows.The recording system corresponds to the archive VTR 4 shown in FIG. 1A.Initially, an input information data DT_(USE) formed of 8 bits as avideo data supplied from the formatter 9 shown in FIG. 1A is input to anouter error code generating circuit 12. As shown in FIG. 3, the outererror code generating circuit 12 generates, with respect to each of datablocks each formed of 118 bytes of the input information data DT_(USE)as a source data 32, parity codes RO₀ to RO₃₀₅ each formed of 10-byteReed-Solomon code as an outer error code (outer error code) 33 by usinga predetermined generating polynomial, and adds the parity codes to eachof the data blocks to output them as an outer data block DO. The outerdata block DO is supplied through a first multiplexer 13 to a memory 14.FIG. 4 shows an arrangement of the memory 14 and a data arrangement inthe memory 14.

As shown in FIG. 4, the memory 14 is formed of memories MEM1, MEM2 whichrespectively have in rows blocks ID40, ID44 each having 1 byte and inputinformation data 41, 45 each having 153 bytes and have in columns outererror codes 42, 46 each having 10 bytes and input information data 43,47 each having 118 bytes. The successively input outer data blocks DO₀to DO₁₅₂ of 153 block amounts are written in the memory MEM1 with dataof one outer data block amount being written in one column, and theoutput data blocks DO₁₅₃ to DO₃₀₅ of 153 block amounts successivelyinput after the outer data blocks DO₀ to DO₁₅₂ are written in the memoryMEM2 with data of one outer data block amount being written in onecolumn.

An information data 43 of one outer data block is formed of 118 bytes.Since the information data of 153 outer data block amount are written ineach of the memories MEM1, MEM2, the information data of a valueobtained from calculation of 118×153×2 bytes, i.e., 36,108 bytes arewritten in the memory 14.

When the data are written in each of columns of the memories MEM1, MEM2,the data are written in the direction A shown in FIG. 4. Lowest 10 bytesof the memories MEM1, MEM2 correspond to the outer error codes 42, 46,respectively.

The memory 14 is supplied through the first multiplexer circuit 13 witha data block identification data ID_(B) which is a data generated by anidentification data generating circuit 15 and used for identifying eachof rows of the memories MEM1, MEM2. Even-numbered data ID_(BE) of thedata block identification data ID_(B) are written in the memory MEM1 inthe order shown by the direction A, and odd-numbered data ID_(BO)thereof are written in the memory MEM2 in the same order.

The data written in the memories MEM1, MEM2 are read from each of therows in the order shown by the direction B with the data of one rowamount being set as one block. When the data are read by a row unit, thedata are read alternately from the memories MEM1, MEM2 in the orderaccording to the data block identification data ID_(B) (00, 01, 02, 03,^(. . .) ). The data read out from the memory MEM1 and the memory MEM2are supplied to an inner error code generating circuit 16.

The inner error code generating circuit 16 generates, with respect toeach of the input data blocks, parity codes RI₀ to RI₂₅₅ each formed ofa 8-byte Reed-Solomon code as an inner error code 52 shown in FIG. 5,and adds the parity codes to an end of each of the data blocks. Then,the inner error code generating circuit supplies added data as innerdata block DI₀ to DI₂₅₅ to a second multiplexer 17.

The second multiplexer 17 successively selects and outputs a preambledata PR and a postamble data PS generated by a preamble-portion andpostamble-portion generating circuit 18 and the inner data block DI₀ toDI₂₅₅ output from the inner error code generating circuit 16. Thepreamble data PR, the inner error data blocks DI₀ to DI₂₅₅, and thepostamble data PS are output in that order.

An output data from the second multiplexer 17 is supplied to a datadispersing circuit 19. The data dispersing circuit 19 disperses(randomizes) the data by exclusive-ORing 1 byte of each input data witha predetermined data.

The dispersed data are supplied to an 8-9 modulating circuit 20. The 8-9modulating circuit 20 converts a data arrangement into that of 8 bits inorder to remove a DC component of a signal waveform recorded on amagnetic tape 25 (to make a signal free from the DC component). Anoutline of this conversion is as follows.

In response to each value of the input data of 1 byte of 8 bits having256 kinds of values, two kinds of 9-bit data are previously determinedby the ID-1 format. These two kinds of 9-bit data are data whose CDSs(Codeword Digital Sums) are reverse to each other in positive andnegative polarities.

The 8-9 modulating circuit 20 monitors a DSV (Digital Sum Variation) ofthe 9-bit data output in response to the input data, and selects eitherof the two kinds of 9-bit data having different CDS values so that thevalue of DSV should be converged. Thus, the input data having a 1-byte,i.e., 8-bit arrangement is converted into the data having the 9-bitarrangement free from the DC component.

The 8-9 modulating circuit 20 includes a circuit for converting an inputdata of NRZL (Nonreturn to Zero Level) format into that of NRZI(Nonreturn to Zero Inverse).

Output data from the 8-9 modulating circuit 20, i.e., the NRZI datahaving 9-bit arrangement are supplied to a third multiplexer 21. Thethird multiplexer 21 adds a synchronization code SYNC_(B) having a fixedlength of 4 bytes generated by a synchronization code generating circuit22, to each data block of the inner data blocks DI₀ to DI₂₅₅ forgenerating synchronization blocks BLK₀ to BLK₂₅₅.

A code pattern of the synchronization code SYNC_(B) is determined by theID-1 format which prescribes that the data thereof recorded on themagnetic tape must have this code pattern.

The data obtained by these processings is shown in FIG. 6 which shows amap thereof. The output data from the third multiplexer 21 has a dataarrangement obtained by scanning a map MAP1 and a map MAP2 in thelateral direction. In FIG. 6, reference numeral 60 depicts the preambleportion PR. Reference numerals 61, 66 depict the synchronization codesSYNC. Reference numerals 62, 67 depict the data block identificationdata ID. Reference numerals 63, 68 depict the information data.Reference numerals 64, 67 depict the outer error codes. Referencenumerals 65, 70 depict the inner error codes. Reference numeral 71depicts the postamble portion PS.

The output data from the third multiplexer 21 is supplied to aparallel-to-serial converting circuit 23. The parallel-to-serialconverting circuit 23 converts the respective input data having a bitparallel arrangement of the preamble portion PR, the synchronizationblocks BLK₀ to BLK₂₅₅ and the postamble portion PS into data S_(REC)having a bit-serial arrangement.

The serial data S_(REC) is amplified by a recording amplifier circuit 24and then supplied as a recording signal to a magnetic head 26 for thehelical scanning on the magnetic tape 25, thereby a recording trackbeing formed on the magnetic tape 25.

Thus, the recording system of the data recorder adds the errorcorrection code to the desired information data DT_(USE) based on theReed-Solomon product code system and then records the information data.

In this embodiment, an operator operates a control panel 27 to therebyset a data of a video-data compression rate N, a recording channel and atape travel speed. The control panel 27 is an operation panel providedon the device 5 for inputting and setting the picture quality that theuser desires the shown in FIG. 1A.

When the video-data compression rate N and the recording channel arerecorded in the user bit on the time code track and the correspondingtape travel speed is properly calculated from the video-data compressionrate N upon reproduction, the video-data compression rate N and therecording channel are set. Accordingly, the video-data compression rateN or data of the tape travel speed is supplied to a tape speed controlunit 29 and a time code recording processing unit 28. The data of therecording channel is supplied to the time code recording processingcircuit 28. The tape speed control unit 29 energize a driver 30 so as tocontrol the tape travel speed based on the data of the tape travel speedcalculated from the data of the tape travel speed or the video datacompression rate N, thereby the tape being traveled at a predeterminedspeed. The time code recording processing unit 28 carries out, based onthe data of the recording channel, data processing required before atime code head 31 records the video-data compression rate N and therecording channel in the user bit on the time code track of the magnetictape 25.

The information data DT_(USE) recorded on the magnetic tape by therecording system of such data recorder are reproduced by a reproducingsystem of the data recorder shown in FIG. 7. The reproducing systemcorresponds to the archive VTR 4 shown in FIG. 1B. The reproducingsystem carries out a signal processing completely reverse to that of therecording system shown in FIG. 2. Specifically, the reproducing systemof this data recorder reads out recording tracks TR ( ^(. . .) , TR1,TR2, TR3, TR4, ^(. . .) ) on the magnetic tape 25 as a reproduced signalS_(PB) by using a magnetic head 26, supplying the reproduced signal to areproduction amplifier circuit 81.

The reproduction amplifier circuit 81 includes an equalizer, abinarizing circuit and so on, and binarizes the supplied reproducedsignal S_(PB) to obtain a reproduced digital data DT_(PB). Then, thereproduction amplifier circuit supplies the reproduced digital data to aserial-to-parallel converting circuit 82 at the succeeding stage. Theserial-to-parallel converting circuit 82 converts the reproduced digitaldata DT_(PB) of serial type into a 9-bit parallel data DT_(PR).

A synchronization code detecting circuit 83 detects the synchronizationcode SYNC_(B) of 4-byte length from a string of the parallel dataDT_(PR), and discriminates the synchronization block based on thesynchronization code. The synchronization code detecting circuitincludes a circuit for converting the parallel data DT_(PR) of NRZIsystem into that of NRZL system.

An output data from the synchronization code detecting circuit 83 issupplied to an 8-9 demodulating circuit 84. The 8-9 demodulating circuit84 restores the 9-bit data, which is obtained in the recording system byconverting the 8-bit data for removing the DC component, to the 8-bitdata again. The 8-9 demodulating circuit 84 is formed of a ROM (ReadOnly Memory) for converting the 8-bit data into the 9-bit data by aretrieval processing.

The data restored to that of 8 bits is subjected by a data integratingcircuit 85 to an integration (de-randomizing) processing reverse to aprocessing of the recording system, i.e., the dispersing processing.This integration is achieved by exclusive-ORing the same predetermineddata as that used for the dispersion processing and a data input to thedata integrating circuit 85.

An inner code error correction circuit 86 subjects the inner data blocksDI₀ to DI₂₅₅ of discriminated synchronization blocks to error detectionand error correction by using the respective 8-bit inner error codes RI₀to RI₂₅₅ added to the blocks.

The inner data blocks DI₀ to DI₂₅₅ subjected to the inner code errorcorrection is written in a memory having the same arrangement as that ofthe memory 14 of the recording system shown in FIG. 6, based on the1-byte block identification data ID_(B) detected by an identificationdata detecting circuit 87 and added to each of the blocks, with one datablock being written in one row of the memory. The writing order issimilar to the order of reading the data blocks from the memory 14 ofthe recording system, i.e., the inner data blocks are alternatelywritten in a memory MEM1 and a memory MEM2 of the memory by a row unitin the order of the block identification data.

The data written in the respective memory MEM1 and memory MEM2 of thememory 88 are read out therefrom in the column direction in the sameorder as the order used when the data is written in the memory 14 of therecording system. As a result, the 128-byte length outer data block DO₀to DO₃₀₅ are obtained again. An outer code error detection andcorrection circuit 89 subjects the outer data blocks DO₀ to DO₃₀₅ outputfrom the memory 88 to error detection and error correction by using therespective 10-byte outer error codes RO₀ to RO₃₀₅ added to the datablocks. Thus, the information data DT_(USE) recorded on the magnetictape 25 are reproduced. The information data DT_(USE) thus reproducedare supplied to the 1:N video-data compression decoder 6 shown in FIG.1B.

In this embodiment, the time code head 31 reads the video-datacompression rate N, the recording channel and the data of the tapetravel speed recorded in the user bit on the time code track of themagnetic tape 25 on the predetermined recording channel.

When upon the recording the video-data compression rate N and therecording channel are recorded in the user bit of the time code trackand upon the recording the corresponding tape travel speed is calculatedfrom the video-data compression rate N, the time code head 31 reads thedata of the video-data compression rate N and the recording channel.

Accordingly, the data of the video-data compression rate N read out bythe time code head 31 are supplied to a video-data compression ratediscriminating circuit 91. The data of the recording channel and thevideo-data compression rate N or the tape travel speed are supplied to atape-travel-speed and channel discrimination control unit 90. Thevideo-data compression rate discriminating circuit 91 supplies atape-travel-speed change data to a tape-travel-speed changing means 92based on the video-data compression rate N. The tape-travel-speed andchannel discrimination control unit 90 supplies a tape-travel-speedchange data to the tape-travel-speed changing means 92 based on the tapetravel speed data calculated from the data of the tape travel speed orthe video-data compression rate N. The tape-travel-speed changing means92 energizes a driver 30, based on the tape-travel-speed change data, tocontrol the tape travel speed, thereby travelling the magnetic tape 25at a predetermined speed.

At this time, the video-data compression rate N discriminated by thevideo-data compression rate discriminating circuit 91 is supplied to the1:N video-data compression decoder 6 shown in FIG. 1B.

The data of the channel input set by the device 8 for inputting andsetting the channel that the user desires shown in FIG. 1B is suppliedto an input terminal 93 provided in the tape-travel-speed and channeldiscrimination control unit 90. With this arrangement, the channel whichthe user desires may be designated by using the user bit on the timecode to reproduce only a video data only on the designated channel.

The embodiment of the recording apparatus and the reproducing apparatusthus arranged according to the present invention is operated as follows.There will hereinafter be described an example of a data recorderDIR-1000 as the archive VTR 4 which changes the tape travel speed inresponse to the data recording speed. This data recorder DIR-1000 isdeveloped by the applicant himself of the present invention andmanufactured on the basis of an “ANSI ID-1” which is a common format inthe world of a data recorder.

In this embodiment, an operation of recording a video data on one trackin accordance with the ID-1 format will be described. FIG. 8A is astructural diagram of one track. As shown in FIG. 8A, 256synchronization blocks 94 are recorded on one track, a preamble 93 and apostamble 94 being respectively recorded thereon before and after thesynchronization blocks. 20 synchronization blocks of the 256synchronization blocks 94 are those of the outer error codes.

The outer error codes are provided by the outer error code generatingcircuit 12 in the recording system shown in FIG. 2. The preamble 93 andthe postamble 95 are generated by the preamble portion and postambleportion generating circuit 18 and added to the synchronization blocks 94by the second multiplexer 17.

FIG. 8B is a structural diagram of one synchronization block. As shownin FIG. 8B, one synchronization block has data 98 of 153 bytes. Asynchronization portion has data of 4 bytes. An ID portion 97 has dataof 1 byte. An inner error code 99 has data of 8 bytes. Accordingly,information of 153×(256−20)=36,108 bytes are recorded on one track.

The inner error code 99 is provided by the inner error code generatingcircuit 16 of the recording system shown in FIG. 2.

FIG. 9 shows a relationship between a recording rate of the datarecorder DIR-1000 and the tape travel speed. As shown in FIG. 9, whenthe recording rate is the highest value, i.e., 1, the tape travel speedis 423.8 [mm/s]. Hereinafter when the recording rate is ½, the tapetravel speed is 211.9 [mm/s]. When the recording rate is ¼, the tapetravel speed is 105.9 [mm/s]. When the recording rate is ⅛, the tapetravel speed is 53.0 [mm/s]. When the recording rate is 1/16, the tapetravel speed is 26.5 [mm/s]. When the recording rate is 1/24, the tapetravel speed is 17.7 [mm/s]. When the recording rate is 1/32, the tapetravel speed is 13.2 [mm/s]. Thus, the tape travel speed is changed atseven steps.

On the other hand, the recording rate of the data recorder DIR-1000 is128 [Mbps] when the tape travel speed is 211.9 [mm/s]. Assuming that atape length for the data recorder DI-1000 is 1,330 [m], it is possibleto keep the recording time of about 100 [minutes].

FIG. 10 shows a relationship among the recording time, the compressionrate and the tape travel speed. When the compression rate is 1, the tapetravel speed is 211.9 [mm/s] and the recording time is 100 [minutes].When the compression rate is ½, the tape travel speed is 105.9 [mm/s]and the recording time is 200 [minutes]. When the compression rate is ¼,the tape travel speed is 53.0 [mm/s] and the recording tim is 400M[minutes]. When the compression rate is ⅛, the tape travel speed is26.5 [mm/s] and the recording time is 800 [minutes]. When thecompression rate is 1/12, the tape travel speed is 17.7 [mm/s] and therecording time is 1200 [minutes]. When the compression rate is 1/16, thetape travel speed is 13.2 [mm/s] and the recording time is 1600[minutes].

When the source tape having the recording time of 100 [minutes] is usedand the compression rate is 1/16, it is possible to store the contentsof the 16 source tapes in one tape for the data recorder DIR-1000. It ispossible to records the contents of the respective source tapes on onetape with different compression rates if the user desires.

On the other hand, since the compression technique is developed day byday, there may be employed a compression technique according to JPEGprocessing a still picture and allowing a transmission rate of 64[kbps], a compression technique according to MPEG-I allowing thetransmission rate of 1.5 [Mbps], and a compression technique accordingto MPEG-II allowing the transmission rate of 5 to 10 [Mbps]. In thiscase, the compression rate is higher than 1/100 and a picture qualityobtained by such compression technique is practically satisfactory.

While in this embodiment the format of the video data is converted froman exiting format thereof to an archive format thereof by using the datarecorder DIR-1000 as the archive VTR 4, it is needless to say that anexiting digital VTR (D1 or the like) other than the data recorder or adata recorder having a new archive format may be employed.

In the above embodiment, it is possible to process the video dataderived from a broadcasting station by wireless, through a transmissionline and so on. In this case, the video data may be supplied to the A/Dconverter 2 shown in FIG. 1A, or the compressed video data may besupplied directly to the archive VTR 4.

According to the above embodiment, since the picture compression rate ischanged by the 1:N video-data compression encoder 3 as the video-datacompression encoding means and the 1:N video-data compression decoder 6as the video-data compression decoding means in response to the picturequality set by the device 5 for inputting and setting the picturequality that the user desires as the picture-quality setting means andthe tape travel speeds of the archive VTR 4 as the recording means andthe archive VTR 4 as the reproducing means are changed in accordancewith the picture compression rate to thereby optionally set the tapetravel speed higher or slower depending upon a level of the picturequality, it is possible to optionally select a tape storage space inresponse to the level of the picture quality.

Further, according to the above embodiment, the source reproducing VTR 1as the video data supplying means reproduces the source tape by the VTR,it is possible to convert the exiting format of the existing source tapeinto the archive format thereof.

Also, according to the above embodiment, since the video data istransmitted through the transmission cable connected to a transmissionsource instead of the source reproducing VTR 1 as the video-datasupplying means, it is possible to utilize the video data from varioussources.

Furthermore, according to the above embodiment, since the video data istransmitted by wireless in the form of the radio wave from thetransmission source instead of the source reproducing VTR 1 as thevideo-data supplying means, it is possible to utilize the video datafrom various sources.

Also, according to the above embodiment, since the archive VTR as thereproducing means 4 retrieves the reproduction channel by retrieving itin accordance with the data recorded in the user bit on the time code onthe tape, even if the video picture is compressed, it is possible todesignate the track and a time axis.

FIG. 11A is a block diagram of another embodiment of the recordingapparatus according to the present invention. In FIG. 11A, a 1-inchomega VTR 110-1 as the source reproducing VTR reproduces an existingsource tape in accordance with an existing format. An A/D converter120-1 converts a video data reproduced by the source reproducing VTR110-1 into a digital value.

A 1:N video-data compression encoder 130-1 is a bit-reduction encoderfor compressing the video data at a rate of 1:N. (where N is a variablevalue and need not be an integer).

Similarly, a 1-inch omega VTR 110-2, an AID converter 120-2 and a 1:Nvideo-data compression encoder 130-2 are provided. X sets of the 1-inchomega VTR, the A/D converter and the 1:N video-data compression encoderare provided up to a 1-inch omega VTR 110-X, an AID converter 120-X anda 1:N video-data compression encoder 130-X. Respective output signalsfrom the 1:N video-data compression encoder 130-1, the 1:N video-datacompression encoder 130-2, ^(. . .) , the 1:N video-data compressionencoder 130-X are supplied to a multiplexer 100. The multiplexer 100time-division multiplexes the respective output signals from the 1:Nvideo-data compression encoder 130-1, the 1:N video-data compressionencoder 130-2, ^(. . .) , the 1:N video-data compression encoder 130-X.

The video data multiplexed by the multiplexer 100 is supplied to anarchive VTR 101 and recorded on the tape thereby. At this time,identification signals of respective source tapes reproduced by the1-inch omega VTR 110-1, the 1-inch omega VTR 110-2, ^(. . .) , the1-inch omega VTR 110-X are recorded on the tape. At this time, theidentification signals may be recorded in the user bit on the time codetrack.

A formatter 9 converts a data format of the video data from the 1-inchomega VTR 110-1, the 1-inch omega VTR 110-2, ^(. . .) , the 1-inch omegaVTR 110-X which are multiplexed by the multiplexer 100 into a dataformat of the archive VTR101. The formatter temporarily writes the videodata of a converted format in a buffer memory incorporated therein andreads out the video data written in the buffer memory to supply thevideo data to the archive VTR101.

A data of a requested picture quality input by the device 5 forinputting and setting the picture quality that the user desires issupplied to the 1:N video-data compression encoder 130-1, the 1:Nvideo-data compression encoder 130-2, ^(. . .) , the 1:N video-datacompression encoder 130-X. The 1:N video-data compression encoder 130-1,the 1:N video-data compression encoder 130-2, ^(. . .) , the 1:Nvideo-data compression encoder 130-X compress the data at the picturecompression rate N corresponding to the requested picture quality. Inaccordance with this compression processing, the archive VTR 101 changesa tape speed in response to the picture compression rate N. The archiveVTR 101 carries out, by simultaneously changing the tape speed and thedrum rotation speed, the control for setting the frequency used for thereproduction the same as the tape recording frequency.

At this time, while it is not necessary to set the video-datacompression rates N of the 1:N video-data compression encoder 130-1, the1:N video-data compression encoder 130-2, ^(. . .) , the 1:N video-datacompression encoder 130-X to the same value, they are usually set to thesame value.

FIG. 11B is a block diagram showing another embodiment of a reproducingapparatus according to the present invention. In FIG. 11B, the archiveVTR 101 reproduces a video data. The video data reproduced by thearchive VTR 101 is supplied to a demultiplexer 102. At this time, eachsource is designated by using a desired-reproduction-source settingdevice 104, the identification signal of each of the designated sourcetapes is reproduced, the designated source is retrieved based thereon,and only the video data of the source tape of the multiplexed video datais output. A 1:N video-data compression decoder 103 is a decoder for Ntimes expanding the video data compressed at the video-data compressionrate N, for restoring the compressed video data supplied from thedemultiplexer 102 to its original picture, whereby a reproduced videosignal is obtained.

A compression technique is developed day and day. In the embodiment, acompression technique according to the MPEG-II is most efficient incompression of a moving picture. When this technique is used, signalsincluding those of ten channels or larger can be recorded on and storedin one tape.

According to the above embodiment, the multiplexer 100 as the video-datamultiplexing means adds the identification signals to a plurality ofdata and converts the plurality of data into a single data. Thedemultiplexer 102 as the video-data demultiplexing means discriminates,based on the identification signals, the video data of the sourcedesignated by the desired-reproduction-source setting device 104 as thereproduction-source designating means and outputs the video data torecord the plurality of video data of the sources on one tape. The videodata of the optional sources are designated and reproduced from onetape. Therefore, it is possible to reduce a tape storage space, andfurther it is possible to reduce a consumed amount of the tape.

FIG. 12 is a block diagram showing a recording apparatus of anotherembodiment of the recording apparatus and reproducing apparatusaccording to the present invention. In this embodiment, the channelnumber of the input video data is set to 16 channels, data of only onechannel is recorded on each track and the data of the same channel isrecorded on every sixteenth channels.

In FIG. 12, picture compression units 201A, 202A, 203A, ^(. . .) , 216Acompress digital video signals of channels 1 to 16, and are formed of,for example, bit reduction encoders or the like. The digital videosignals of channel channels 1 to 16 compressed by the picturecompression units 201A, 202A, 203A, ^(. . .) , 216A are supplied toencoding units 201B, 202B, 203B, ^(. . .) , 216B.

The encoding units 201B, 202B, 203B, ^(. . .) , 216B generates errorcorrection codes and so on for digital signal processings. In thedigital signal processings, the signal of each channel is digitallyprocessed, and the processings of the data of the respective channelsare completely independent of one another.

The digital video signals of channels 1 to 16 encoded by the encodingunits 201B, 202B, 203B, ^(. . .) , 216B are supplied to memory units201C, 202C, 203C, ^(. . .) , 216C. The memory units 201C, 202C, 203C,^(. . .) , 216C temporarily stores the digital video signals of channels1 to 16.

The digital video signal stored in the memory units 201C, 202C, 203C,^(. . .) , 216C are supplied to a signal selection unit 217. Arecording-signal timing control unit 218 controls the memory units 201C,202C, 203C, ^(. . .) , 216C and the signal selection unit 217. FIG. 14shows a track formed on the tape according to an embodiment of therecording apparatus and reproducing apparatus of the present invention.A track 300 is successively formed in a tape length direction. Signalsfor respective channels are output to recording heads A, B, C, D so thatthe signal of the same channel should be recorded on every sixteenthtracks. The recording heads record the signals on a tape traveled by atape drive unit, not shown, in accordance with a recording format of theabove tracks.

In this embodiment, when the channel number of the input video data issixteen and the video-data compression rates of the picture compressionunits 201A, 202A, 203A, ^(. . .) , 216A are 1/16, an archive VTR canrecord the video data at one-fold speed. When the channel number of theinput video data is sixteen and the video-data compression rates of thepicture compression units 201A, 202A, 203A, ^(. . .) , 216A are 1/32,the archive VTR can record the video data at ½-fold speed.

In this embodiment, since the data obtained when the tape is traveled byan amount of 16 tracks is recorded on one track, it is sufficient foreach of the memory units 201C, 202C, 203C, ^(. . .) , 216C to have acapacity twice as much as the data of one track amount. At this time,when the number of the recording heads A, B, C, D is the same as thechannel number, it is unnecessary to provide the signal selection unit217 shown in FIG. 12 and signals output from the memory units 201C,202C, 203C, ^(. . .) , 216C may be supplied to the recording heads A, B,C, D as they are and recorded on the tape.

However, when the number of the recording heads A, B, C, D are largerthan the channel number, it is physically difficult to mount the drumwith the recording heads which are as much as the channel number, andthis arrangement costs very high. Therefore, in general, the number ofthe recording heads A, B, C, D is properly set to about 8 to 16.

In this embodiment, as shown in FIG. 15, a drum of four-head system isemployed. In order to record data of four channels, the recording headsA, B, C, D are provided with the recording heads A, B for 2 channels andthe recording heads C, D for 2 channels being respectively paired andthe respective two pairs of the recording heads A, B and C, D beingprovided at an outer peripheral end portion of a drum 400 so as tooppose to each other at an angle of 180°. In order to reproduce data offour channels, reproducing heads A′, B′, C′, D′ are provided with thereproducing heads A′, B′ for 2 channels and the reproducing heads C′, D′for 2 channels being respectively paired and the respective two pairs ofthe reproducing heads A′, B′ and C′, D′ being provided at the outerperipheral end portion of the drum 400 so as to oppose to each other atan angle of 180°.

The recording heads A, B and C, D are respectively provided at positionspreceding to those of the reproducing heads A′, B′ and C′, D′ by 90° inthe rotation direction of the drum 400 shown by an arrow in the figure.This arrangement allows the reproducing heads A′, B′ and C′, D′ toreproduce the data for monitoring at the same time when the recordingheads A, B and C, D record the data, i.e., to serve as so-calledconfidence heads. Erase heads A″, B″ and C″, D″ are respectivelyprovided at positions preceding to the recording heads A, B and C, D by45° in the rotation direction of the drum 400 shown by the arrow in thefigure.

FIG. 18 is a detailed block diagram of the signal selection unit 217. Arecording signal selection unit A1 supplies a single recording signal ofthe compressed data of respective channels 1, 5, 9, 13 to the recordinghead A based on a recording gate signal G-1 from the recording head Aand a recording selection signal A-1 from the recording-signal timingcontrol unit 218. A recording signal selection unit B1 supplies a singlerecording signal of the compressed data of respective channels 2, 6, 10,14 to the recording head B based on a recording gate signal G-2 from therecording head B and a recording selection signal A-2 from therecording-signal timing control unit 218.

A recording signal selection unit C1 supplies a single recording signalof the compressed data of respective channels 3, 7, 11, 15 to therecording head C based on a recording gate signal G-3 from the recordinghead C and a recording selection signal B-1 from the recording-signaltiming control unit 218. A recording signal selection unit D1 supplies asingle recording signal of the compressed data of respective channels 3,7, 11, 15 to the recording head D based on a recording gate signal G-4from the recording head D and a recording selection signal B-2 from therecording-signal timing control unit 218.

FIG. 19 shows a timing chart of control of the signal selection unit217. As the drum is rotated, the recording heads A, B and C, D as twopairs are respectively rotated. Thus, the recording heads A, B and C, Drecord the data on the tracks for respective channels based on therecording selection signals A-1, A-2, B-1 and B-2 and the gate signals.

As described above, the data for channels to be recorded by therecording heads are input to the recording signal selection units forrespective recording heads, and a signal output from each of the signalselection units is selected based on the recording selection signal.Since it is sufficient for each of the selection units to select oneoutput signal from the four input signals, this selection can becontrolled by using the 2-bit selection signal. In this embodiment,while each pair of the recording heads A, B and C, D is controlled byusing the same selection signal, only the selection signal of one systemis required when the track is formed during a half rotation of the drum.

At this time, assuming that the number of the channels on which thesingle head records data, i.e., the number of the channels on which thesingle head records the data at the same time is 4, it is sufficient foreach of the picture compression units 201A, 202A, 203A, ^(. . .) , 216A,the encoding units 201B, 202B, 203B, ^(. . .) , 216B, and the memoryunits 201C, 202C, 203C, ^(. . .) , 216C shown in FIG. 12 to haveprocessing units for 4 channels of 16 channels.

If the timing signal is controlled, then it is sufficient to provide therecording signal selection unit shown in FIG. 18 of one channel amount.Specifically, when a compression VTR capable of recording data of 16channels with using four heads records the data of four channels in eachof four recording operations, the recording signal selection unit mayhave input processing units for four channels and a recording processingunit for one channel.

FIG. 13 is a block diagram showing a reproducing apparatus of theembodiment of the recording apparatus and reproducing apparatusaccording to the present invention. As shown in FIG. 13, signalsreproduced by reproducing heads A, B, C, D are divided by a signaldividing unit 219 into the signals for the respective channels 1 to 16.

The signals for the respective channels 1 to 16 obtained by dividing thesignals by the signal dividing unit 219 are supplied to memory units.The memory units 221D, 222D, 223D, ^(. . .) , 236D store the respectivesignals to adjust phases of output signals. These controls are carriedout by a reproduced-signal timing control unit 220.

The output signals from the memory units 221D, 222D, 223D, ^(. . .) ,236D are supplied to decoding units 221E, 222E, 223E, ^(. . .) , 236E,respectively. The decoding units 221E, 222E, 223E, ^(. . .) , 236E carryout signal processing such as error correction or the like.

The respective signals subjected by the decoding units 221E, 222E, 223E,^(. . .) , 236E to the error correction are supplied to pictureexpanding units 221F, 222F, 223F, ^(. . .) , 236F. The picture expandingunits 221F, 222F, 223F, ^(. . .) , 236F carry out signal processings forrestoring the supplied signals to their original pictures. Thus, thedigital video signals of the respective channels 1 to 16 are output.

In this embodiment, since the video signals for sixteen channels can besimultaneously recorded, a time required for the recording is reduced toa time which is 1/16 time as much as a time required for the successiverecording. Since the data for the respective channels are not mixed onthe track, if the reproducing VTRs of the number which is less thansixteen, e.g., four are provided when data of the sixteen recorded tapeare compressed and recorded, it is possible to easily record the data ofall the sixteen recorded tapes by repeatedly recording data of fourchannels at each of four recording operations.

Specifically, the data may be recorded, for example, such that at thefirst recording, signals for channels 1, 5, 9, 13 are supplied to fourVTRs and only these signals are recorded thereon and hereinafter thedata for channels 2, 6, 10, 14, for channels 3, 7, 11, 15 and forchannels 4, 8, 12, 16 are successively recorded.

Tracks may be formed as shown in FIG. 16 by respectively providing anupper track 500 and a lower track 510 in the tape width direction withtracks for even-numbered channels and tracks for odd-numbered channelsbeing respectively formed on the upper track 500 and the lower track510.

In this case, a space used for edition may be provided between the dataof the respective channels, a circuit for controlling a timing of theedition being provided similarly to the recording-signal timing controlunit 218 shown in FIG. 12.

If it is easy to edit the channels as described in the above embodiment,each of the signal processings can flexibly be carried out withoutpreparing the reproducing apparatus of the number equal to the channelnumber.

When so-called DT (dynamic tracking) heads used for variable-speedreproduction by changing a head height by its bimorph structure areemployed as the reproducing heads A, B, C, D shown in FIG. 15, it ispossible to reproduce the recorded data of optional channels at highspeed without changing the drum rotation speed upon the high-speedreproduction.

In the above embodiment, if heads capable of independently scanningtracks apart from each other by sixteen tracks are employed as the fourreproducing heads A, B, C, D, it is possible to reproduce the data ofthe four optional channels of the sixteen channels at the four-foldspeed.

While the tape is usually traveled by four-track amounts during one drumrotation upon the normal reproduction, the tape is travelled bysixteen-track amounts when the data is reproduced at the four-foldspeed. The four independent DT heads capable of independently scanningtracks apart from each other by sixteen tracks can reproduce the data ofthe four optional tracks of the sixteen tracks, i.e., the data of fourchannels during one rotation. Accordingly, it is possible tocontinuously reproduce the data of four channels at the four-fold speed.

These heads are effective when the compressed data are transferred fordubbing to a recording apparatus capable of high-speed recording such asa disk recording apparatus or the like. In this case, the data may beoutput from the decoding units 221E, 222E, 223E, ^(. . .) , 236E shownin FIG. 13.

If the picture expanding units 221F, 222F, 223F, ^(. . .) , 236F shownin FIG. 13 can process the data at four-fold speed, it is possible toreproduce the original picture at four-fold speed. However, it isdifficult to expand the data at high speed with a general technique atpresent.

However, when the data is compressed by a certain unit, if each of thecapacities of the memory units 221D, 222D, 223D, ^(. . .) , 236D shownin FIG. 13 is larger than the unit of the data, then it is possible toreproduce the original picture at four-fold speed by distributing thereproduced data to the memories of the reproducing systems having thechannels not used for reproduction upon the reproduction at four-foldspeed and carrying out the decoding and picture-expanding processings bythe decoding units 221E, 222E, 223E, ^(. . .) , 236E and the pictureexpanding units 221F, 222F, 223F, ^(. . .) , 236F of those channels tosynthesize the signals output therefrom.

A reproducing apparatus used in this case is arranged as shown in FIG.17. In FIG. 17 which is a block diagram of the reproducing apparatus,the reproducing apparatus is different from that shown in FIG. 13 inthat a signal synthesizing unit 600 is provided at the succeeding stageof the picture expanding units. At this time, if the pictures of everyfourth frames are successively output, for example, then the reproducingapparatus is effective in the high-speed search mode. A memory forstoring data of a data-compression unit is provided in each of thepicture expanding units, the data being divided into those of respectivechannels at the succeeding stages of the decoding unit.

In this embodiment, when each of data strings can be recorded for twohours, if a data string is desired to be recorded for a time more thantwo hours, then it is possible to easily record the data up to fourhours by recording the data on two tracks of the sixteen tracks.

Thus, it is possible to effectively, drastically reduce a storage spaceby compressing and storing a large amount of data such as those of alibrary in a broadcasting station. If the above recording system isemployed as a backup of a disk apparatus for recording the compresseddata or the like, then even when a part of the data of the disk isbroken, it is possible to restore the broken data within a short periodby using the high-speed dubbing.

In FIG. 12, the picture compression units 201A, 202A, 203A, ^(. . .) ,216A may employ the compression technique according to JPEG dealing withthe still picture and allowing the transmission rate of 64 [kbps], thecompression technique according to MPEG-I allowing the transmission rateof 1.5 [Mbps] and the compression technique according to MPEG-IIallowing the transmission rate of 5 to 10 [Mbps]. In this case, thecompression rate is more than 1/100, and the picture quality of thecompressed data is practically satisfactory. In this embodiment, theMPEG-II is most efficient in compression of the moving picture. Use ofthis compression technique allows the signals of ten channels or more tobe recorded on and stored in one tape.

In this embodiment, the video data transmitted from the broadcastingstation in the form of a radio wave or derived through a transmissioncable or the like can be used as the digital video signals for channels1 to 16. In this case, A/D converters may be provided at the precedingstages of the picture compression units 201A, 202A, 203A, ^(. . .) ,216A shown in FIG. 12, for inputting an analog video signal to theformer. The video data previously compressed may be supplied directly tothe encoding units 201B, 202B, 203B, ^(. . .) , 216B.

In the above embodiment, a digital VTR may be employed as the archiveVTR using the recording heads A, B, C, D and the reproducing heads A, B,C, D to record the video data. Since the compressed video data isrecorded and reproduced, it is sufficient that it can be used as thedata recorder.

According to the above embodiment, since the track 300 is formed in thetape length direction in response to each channel for a data stringobtained from the digital video signals as the video data and the tracks300 are independently formed at a predetermined constant interval byrecording data by the plurality of recording heads A, B, C, D, data ofthe plurality of tracks 300 can be simultaneously recorded andreproduced, and data of a part of the tracks 300 can easily be recordedafter other tracks are used for the recording.

According to the above embodiment, when the number of the channels 1 to16 of the digital video signals as the video data is larger than thenumber of the plurality of recording heads A, B, C and D, each of therecording heads A, B, C, D records data strings of specific channels ofthe channels 1 to 16 on the specific plural tracks 300 of the tracks 300each corresponding to each of the channels 1 to 16 and formed in thetape length direction. Therefore, it is possible for each of therecording heads A, B, C, D to record the data of specific channels ofthe channels 1 to 16 on the corresponding tracks 300 within onerecording operation.

According to the above embodiment, when the number of the channels 1 to16 of the digital video signals as the video data is larger than thenumber of the plurality of recording heads A, B, C and D, the datastrings of the digital video signals are recorded and the tracks 300 areformed in the tape length direction and the tape width direction torecord the data of the specific channels of the channels 1 to 16 on thecorresponding plural tracks 300. Therefore, it is possible tosimultaneously record the data by the recording heads A, B, C, D of thesmall number even if the data has a large number of channels.

According to the above embodiment, since the plurality of recordingheads A, B, C, D simultaneously record a plurality of data strings onthe tracks 300 and the plurality of reproducing heads A′, B′, C′ and D′reproduce the data recorded on the plurality of tracks 300 at a speedmultiplied by a predetermined number by setting the rotation speed ofthe drum 400 constant, it is possible to reduce the recording time, andfurther it is possible to reproduce the data recorded on the optionaltracks 300 on the tape at high speed.

According to the above embodiment, since the plurality of recordingheads A, B, C, D are provided so as to record the data of four channelswith two recording heads thereof being paired respectively and one pairof the recording heads A, B and the other pair of recording heads C, Dbeing provided at the outer peripheral end portion of the drum 400 so asto oppose to each other at the angle of 180° and the plurality ofreproducing heads A′, B′, C′, D′ are provided so as to reproduce thedata of four channels with two reproducing heads thereof being pairedrespectively and one pair of the reproducing heads A′, B′ and the otherpair of reproducing heads C′, D′ being provided at the outer peripheralend portion of the drum 400 so as to oppose to each other at the angleof 180°, it is possible to record the data of the channels of the four'smultiple during a plurality of rotation of the drum 400 by recording thedata of four channels per one rotation of the drum 400.

According to the above embodiment, since the recording timing controlunit 218 as the recording timing control means for controlling thetiming used for recording the digital video signal as the video data ofthe channels 1 to 16 compressed by the picture compression units 201A,202A, 203A, ^(. . .) , 216A on the tape is provided between the picturecompression units 201A, 202A, 203A, ^(. . .) , 216A as the video-datacompression means and the plurality of recording heads A, B, C, D andthe respective tracks 300 where the data strings of the same channel arerecorded at an interval of the predetermined tracks are formed under thecontrol of the recording timing control unit 218, it is possible toallocate the channel of a predetermined number to each of the tracks300.

According to the above embodiment, when the number of the plurality ofreproducing heads A′, B′, C′, D′ is four and the number of the tracks300 for a plurality of data strings is 16 tracks, each of thereproducing heads A′, B′, C′, D′ scans the every sixteenth tracks,thereby the data recorded on the tracks of four optional channels of the16-channel tracks being reproduced at four-fold speed. Therefore, thedata of the four optional tracks of the 16 tracks, i.e., the data offour channels can be reproduced per one rotation of the drum 40, whichallows the continuous reproduction at four-fold speed.

INDUSTRIAL APPLICABILITY

The recording apparatus and the reproducing apparatus according to thepresent invention are suitable for the archive recording and reproducingapparatus for keeping a source tape retained for reproduction in abroadcasting station or the like.

1-8. (canceled)
 9. A recording apparatus being characterized bycomprising: a video-data supply means for supplying a video data; acompression means for compressing said video data; a setting means forsetting a compression rate used in said compression means; a controlmeans for controlling a travel speed of a recording medium so that saidrecording medium should be traveled at a speed corresponding to saidcompression rate set by said setting means; and a recording means forrecording said video data compressed by said compression means on saidrecording medium, wherein the recording media is tape-type media.